Wire coil



P 1956 H. w. STERNBERG ETAL 3,

WIRE c011,

Filed Feb. 17, 1965 5 Sheets-Sheet 1 F/G. H6 2 /IIH r INVENTORS. HUOT W. STERNBERG HARRY G. ROBINSON ATTORNE Y5 P 1966 H. w. STERNBERG ETAL 3,272,455

WIRE COIL Filed Feb. 17, 1965 5 Sheets-Sheet Z INVENTORS.

HUOT W. STERNBERG HARRY G. ROBINSON ATTORNEYS Sept. 13, 1966 Filed Feb. 17, 1965 H. W. STERNBERG ETAL WIRE COIL 3 Sheets-Sheet 3 FIG. 5

68 l 74- ,s o 7 W I I 66 )Q g K INVENTORS HUOT w. STERNBiERG HARRY G. ROBINSON ATTORNEYS United States Patent York Filed Feb. 17, 1965, Ser. No. 437,619 3 Claims. (Cl. 242171) This application is a continuation-in-part of our prior application Serial No. 391,146, filed August 21, 1964, now abandoned, which in turn is a continuation-in-part of our prior application Serial No. 346,811, filed February 24, 1964, now abandoned.

This invention relates to wire coiling, and in particular to the formation of coils from which wire can be withdrawn without bodily rotation of the coil.

The manufacture of wire entails coiling or spooling between processes and, of course, the final product must be delivered in some package from which it can be with drawn. Despite many elaborate developments, winding of wire, especially when it entails unwinding from another reel, is a relatively expensive procedure, because of the labor and supervision required. 'In the case of fine wire, this is particularly noticeable, as the inertia of the supply reel, if large, is so great that very accurate control of its rotational speed is required to maintain the wire at proper tension and to prevent either overrunning or snapping of the wire.

There are a large number of utilization processes which require wire withdrawal from a package at non-uniform velocity. If the package is a reel, considerable machinery is required to rotate the reel at a suitable speed to prevent snarling of the wire or undue stress on the wire as it is withdrawn from the reel. Even in those applications where lengths of wire are withdrawn from a reel by hand, as part of a manufacturing or assembling operation, a heavy reel slows up the operation to a considerable extent.

In the case of dead wire, such as copper conductors, relatively small coils can be withdrawn from packages in the manner of twine from balls, that is, from the interior of the coil. Very large coils of ferrous wire have been arranged in drums, of as much as five hundred pounds in capacity, for withdrawal in an axial direction from the drum through mechanisms which nullify the twist engendered by such withdrawal.

However, there are many wire products, including filamentary wire, strand, rope and cable, which cannot be so treated. In the case of these materials, it has been suggested that the wire product be made up into a package in the general form of a helical coil, the wire having, in its packaged form, one twist per convolution. That is to say, the wire is coiled in some fashion, and at the same time twisted, so that upon withdrawal the twist in the wire will neutralize the twist engendered by axial withdrawal of the wire and the wire will be delivered without torsional stress.

Many packages of wire have been made for special purposes in the form of helical coils, with the above-specified twist, but the only successful ones have been those which are wound in level, even layers on a mandrel which is afterwards removed. In such an arrangement, the tightly compacted turns are supposed to mutually support each other until the wire is withdrawn. Despite the utmost care in winding, however, provision must be made for convolutions ahead of the one being unwound which come loose from the wound mass. The ordinary way for taking care of such prematurely unwound convolutions is to provide a center post within the coil to prevent such convolutions from snarling with the portion of the wire leaving the package. Such a center post does lessen the tendency to snarl but does not prevent it.

We have found that it is possible to make a package of wire with a twist of substantially one turn per convolution, and to withdraw wire from such a package without danger of snarling. The principle is applicable to all kinds of wire line, subject to modification only because of the physical characteristics of the material being handled. As will become apparent later, the present invention is concerned with materials having a certain degree of elasticity and does not have to do with materials such as soft copper wire, solder or the like. Plastic rods and tubes are also within the purview of this invention, provided they have enough elasticity and flexibility to act as wire when coiled and twisted.

Broadly, the invention is directed to a package of Wire comprising an annular container and a coil of wire disposed in a multiplicity of overlying convolutions within the container. Each convolution of the wire has substantially one elastic back twist permitting it to be withdrawn axially from the container free of net torsional deformation. Each convolution of the wire also presses outwardly within the container to retain adjacent convolutions against entangling displacement prior to and during withdrawal of the wire. In addition, the package may also be provided with exit guide means on the container defining a curved guide path for the wire to prevent the transmission of torsional forces from withdrawn portions of the wire .back to the convolutions of the Wire remaining in the container.

The method of the invention is applicable to the manufacture of a wire coil from which the wire can be withdrawn free of net torsional deformation. It involves pushing the wire longitudinally into peripheral containing means in an initial path generally parallel to the containing means axis. The wire is restrained from rotation about its axis where it is being pushed forward. At the same time the moving wire is guided from its initial path into a curved path sweeping around the inside of the containing means, so that successive convolutions of the wire each having one elastic back twist are formed in the containing means. Apparatus for carrying out this method is also provided comprising drive means for pushing a length of th wire forward toward an annular package in an initially straight path of travel without permitting the wire to rotate about its axis where the pushing force is exerted. Means are also included for directing the wire from its straight path of travel into a curved path sweeping around the inside of the package, so that successive convolutions of back twisted wire are laid within the package.

The present invention requires that packages of wire be made a certain way, and that the wire be withdrawn a certain way. If the packages are made as prescribed, they have a characteristic action upon unwinding which is different from that of packages or coils manufactured by different means or methods.

Referring now to the drawings:

FIG. 1 is a section of one form of package, consisting essentially of a cylindrical container with a coil of wire therein;

FIG. 2 is a section of the package of FIG. 1, showing one mode of withdrawal of the wire therefrom;

FIG. 3 is a section of a package similar to that shown in FIG. 1, but with finer wire, and a diflerent mode of withdrawal;

FIG. 3A is a section taken along the line 3A-3A of FIG. 3;

FIG. 4 is a generalized showing of a packaging mechanism which is adaptable to a wide range of wire materials;

FIG. 4A is a section partly broken away and taken along the line 4A-4A of FIG. 4;

FIG. is another embodiment of the package shown in FIG. 2 illustrating a modified exit guide means; and

FIG. 6 is another embodiment of the exit guide means of FIG. 2.

In order to make such a coil, it is necessary, of course, that the convolutions be of sufficient circumference that the twist imparted to the wire does not exceed the elastic limit of the wire in torsion, which limits the minimum diameter of the coil. If it is desired to have the wire without a cast, the minimum diameter of the coil would be limited by this factor also. However, as far as has been determined, cast in the wire does not seriously affect the ability of the Wire to be withdrawn from the contemplated packages without snarling.

Referring now to FIG. 1, a package of wire according to the present inveniton is shown. It consists simply of a cylindrical container 10 having a central hole 11 in one end wall, through which the wire is to be Withdrawn. The inner end 12 of the wire is secured to some part of the container to prevent its displacement and additionally to prevent its rotating or untwisting.

It will be understood of course that the container can be metal or any other material sufliciently strong, such as corrugated board, and that with wire of the right characteristics, the container can be square or otherwise polygonal in shape, rather than circular. It is necessary, however, that it be capable of resisting the force tending to burst it as the wire is pushed into place. As a practical matter, a container of suflicient strength to permit transportation of a wire coil of the weight involved is strong enough to prevent such bursting.

In order'to produce such a package of wire, the simplest procedure is to hold the container against rotation, and feed wire into the container in such a manner that a force is generated putting the wire under compression. At the same time, a twist must be imparted to the wire. Any distribution system, to assure that the wire is deposited in layers, may be used. As an example, in FIG. 4 the container 10 is clamped to a carriage 20, which is reciprocated along the rods 21 by means of a hydraulic cylinder 22. A tube 23 leads the wire from reel 24 to the interior of the container. This tube has a substantially helical configuration, as can be seen by comparing FIGS. 4 and 4a, so that at the end nearest the coil, it is pointed almost tangent to the smallest diameter convolution which is to be produced by the machine.

The tube 23 is mounted to rotate in bearings 25 and 26. That being so, forcing wire 27 through the tube will cause the tube to rotate in the direction shown in FIG. 4a, resulting in laying of the wire inside the container in coiled form. Such forcing of the wire through the tube can be done by means of a series of rollers engaging the wire, as the rollers 28. These rollers perform two functions. They of course drive the wire through the tube, and also prevent the twist engendered by the coiling from travelling back to the supply reel 24. After it passes the rollers, the Wire takes on some torsional deformation as it travels to the coil, at which point it has a twist of one turn per convolution.

It was mentioned that it is necessary that the wire be under compression in the container. For this purpose, it is merely necessary to apply a retaining torque to the tube 23. A brake 30, as simple or elaborate as may be required, is all that is necessary to produce such compressive stress in the wire.

It is to be understood that considerable variations in the mechanism shown in FIG. 4 is possible. For instance, in the case of very fine Wire, it may be necessary 'to make the discharge end of the tube flexible so that the mouth can be close to or resting on the surface of the container or the coil of wire, thus minimizing the tendency of the wire to buckle before it is in place in the coil.

Because the wire in the package is under a state of elastic deformation, it tends to relieve itself by leaving the package if the inner end is threaded through the opening and prevented from turning. Depending on the size and elasticity of the Wire, the amount of guidance and restraint required to make it leave the package varies considerably. In FIG. 2 a simple collar 40, secured to a spider 41 cooperates with the opening of the container to assure correct Withdrawal. If desired, the collar may be provided with a bushing or other means to prevent spontaneous ejection of the wire by generating sutficient drag. It has been found that with such an arrangement the wire takes the form of a helix Wrapped on a cone, or some surface of revolution larger at the inner end than the other. Because of the interplay between the torsional elasticity and the bending elasticity of the wire, the helix is remarkably stable, and the wire in the coil is not displaced except to leave the coil along the helical path so defined. This helix, by the way, is the optimum shape of the tube utilized in making the coils in the machine of FIG. 4.

Some wire requires more guidance on removal than the arrangement shown in FIG. 2. In FIG. 3 one form of guide is shown consisting of a cone shaped rotating member mounted in bearing 50, coaxial with a bearing 52 in the container support 53 on which the container of wire is rotatably mounted. For the purpose of providing guidance, a tube 54 is secured to the inside of the cone and connects with the center bore of the axial rotatable tube 55. The tube 54 may extend into the package, with the section 56 either rigid or somewhat flexible, depending on what the wire in the package requires. This tube should be in the form of a helix, in order to permit the wire to take the form it naturally takes when unconfined.

The exit guide means illustrated in FIGS. 5 and 6 are similar to those illustrated in FIGS. 2 and 3 but are specifically designed to prevent torsional feed back into the package. It has been found with certain uses of the wire that undesired torsional forces are created in portions of the wire outside of the package which forces tend to be directed back into the package thereby upsetting the package coils. For example, where a welding wire is extended a substantial distance from the package and directed in and around a large workpiece the wire tends to become looped or coiled as a result of such use. Such coiling generates torsional forces in the wire which may be translated back into the package and cause upsetment of the coils there.

To prevent such feed back the exit guide means on the container defines, generally, a curved guide path for the Wire. Specifically referring to FIG. 5, a U-shaped tube 60 is secured to the container by a spider 62. The tube 60 provides curved guide path through which the Wire passes. The wire 64 may still be withdrawn from the package in an untwisted condition. However, those withdrawn portions of the wire outside the package which may become twisted during use cannot transmit the forces tending to cast loops in the Wire back into the package because of the interposition of the tube 60.

Torsional feed back is also prevented by the exit guide means shown in FIG. 6. There a plurality of rollers 66 offset with respect to each other, guide the wire in a curved course or path as it is withdrawn. The rollers 66 are supported by a bracket 68 secured to the container. This guide means is similar to that of FIG. 5 but has the advantage of offering lower resistance to the withdrawal of the wire.

From what has been said above, it is evident that although it may be theoretically possible to specify a particular winding and unwinding arrangement, given the size of the package, size, stiffness and torsional stiffness of the wire to be packaged and dispensed, a much easier method is to produce a package by some makeshift arrangement and observe its action as the wire is with drawn. The amount of support needed soon becomes evident.

Although the word wire is used throughout this specification, it is intended to include strand rope or cable having torsional elasticity as well as a filamentary wire. Also, the structure need not be metallic, as set forth above, but can as well be, for example, glass or organic material, provided it also has the required elasticity.

The torsional deformation of the wire has been described as one turn per convolution. Strictly speaking, the amount of deformation is a function of the angle the wire makes with a plane perpendicular to the axis of the coil. This angle is very nearly a right one, and accordingly the deformation is for all practical purposes as described. If the wire is coiled with rapid traverse, it will have a torsional deformation different from that described. The method of manufacture described, however, automatically takes care of this, the wire taking more or less twist per convolution as required to come out in an untwisted condition.

We claim:

1. In a wire package which includes an annular container and a coil of wire disposed therewithin in a multiplicity of overlying convolutions pressing outwardly against the container and having substantially one elastic back twist per convolution permitting axial withdrawal of the wire from the container free of net torsional deformation, means for preventing transmission of torsional forces from withdrawn portions of the wire back to convolutions remaining in the container comprising (a) exit guide means mounted on the container to initially guide the withdrawn portion of the wire along the axis of the container, then in a curved path away from and then back along the container axis,

(b) said curved path being fixed with respect to the container and differing from any free path otherwise taken by the wire when axially withdrawn from the container without engaging the exit guide means.

2. A package according to claim 1 wherein the exit guide means comprises a tube fixed to the container through which the wire is withdrawn, said tube having end portions substantially coaxial with the container axis and an intermediate substantially U-shaped portion.

3. A package according to claim 1 wherein the exit guide means comprises a plurality of opposed rollers through which the wire is withdrawn, said rollers being rotatably mounted on respective axes fixed with respect to the container and being offset to guide the withdrawn wire initially along the axis of the container, then in a curved path away from and then back along the container axis.

References Cited by the Examiner UNITED STATES PATENTS 302,362 7/1884 Sweet 24283 1,063,646 6/1913 Bournonville 242171 1,295,717 2/1919 Erickson 242137.1 1,343,238 6/1920 Taylor 242-171 1,864,267 6/1932 Baker et al. 2- 242105 1,985,603 12/1934 Elssner 24218 2,220,481 11/ 1940 Fritts 24283 2,319,828 5/1943 Rohweder 242128 2,428,002 9/ 1947 Barrett 24283 X 2,892,899 6/1959 Connell 24283 X 3,028,109 4/1962 Golub 24218 FOREIGN PATENTS 924,409 4/ 1963 Great Britain.

STANLEY N. GILREATH, Primary Examiner. 

1. IN A WIRE PACKAGE WHICH INCLUDES AN ANNULAR CONTAINER AND A COIL OF WIRE DISPOSED THEREWITHIN IN A MULTIPLICITY OF OVERLYING CONVOLUTIONS PRESSING OUTWARDLY AGAINST THE CONTAINER AND HAVING SUBSTANTIALLY ONE ELASTIC BACK TWIST PER CONVOLUTION PERMITTING AXIAL WITHDRAWAL OF THE WIRE FROM THE CONTAINER FREE OF NET TORSIONAL DEFORMATION, MEANS FOR PREVENTING TRANSMISSION OF TORSIONAL FORCES FROM WITHDRAWN PORTIONS OF THE WIRE BACK TO CONVOLUTIONS REMAINING IN THE CONTAINER COMPRISING (A) EXIT GUIDE MEANS MOUNTED ON THE CONTAINER TO INITIALLY GUIDE THE WITHDRAWN PORTION OF THE WIRE ALONG THE AXIS OF THE CONTAINER, THEN IN A CURVED PATH AWAY FROM AND THEN BACK ALONG THE CONTAINER AXIS, (B) SAID CURVED PATH BEING FIXED WITH RESPECT TO THE CONTAINER AND DIFFERING FROM ANY FREE PATH OTHERWISE TAKEN BY THE WIRE WHEN AXIALLY WITHDRAWN FROM THE CONTAINER WITHOUT ENGAGING THE EXIT GUIDE MEANS. 